(3) attempts by physical menace to put another in fear of imminent serious bodily injury; or

(4) conceals or attempts to conceal a hypodermic needle on his person and intentionally or knowingly penetrates a law enforcement officer or an officer or an employee of a correctional institution, county jail or prison, detention facility or mental hospital during the course of an arrest or any search of the person.

(b) Grading. — Simple assault is a misdemeanor of the second degree unless committed:

(1) in a fight or scuffle entered into by mutual consent, in which case it is a misdemeanor of the third degree; or

(2) against a child under 12 years of age by a person 18 years of age or older, in which case it is a misdemeanor of the first degree.